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Yasuhiro Yamashita - One of the best experts on this subject based on the ideXlab platform.
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catalytic stereoselective 1 4 addition reactions using csf on alumina as a solid base continuous flow synthesis of Glutamic Acid Derivatives
Angewandte Chemie, 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shū KobayashiAbstract:A novel methodology using CsF⋅Al2O3 as a highly efficient, environmentally benign, and reusable solid-base catalyst was developed to synthesize Glutamic Acid Derivatives by stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF⋅Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing the undesired formation of pyrrolidine derivations by [3+2] cycloadditions, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR and 19F NMR spectroscopy, FT-IR, CO2-TPD, and XPS. And highly basic F from Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using this solid-base catalysis.
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Catalytic Stereoselective 1,4‐Addition Reactions Using CsF on Alumina as a Solid Base: Continuous‐Flow Synthesis of Glutamic Acid Derivatives
Angewandte Chemie (International ed. in English), 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shū KobayashiAbstract:A novel methodology using CsF⋅Al2O3 as a highly efficient, environmentally benign, and reusable solid-base catalyst was developed to synthesize Glutamic Acid Derivatives by stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF⋅Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing the undesired formation of pyrrolidine derivations by [3+2] cycloadditions, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR and 19F NMR spectroscopy, FT-IR, CO2-TPD, and XPS. And highly basic F from Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using this solid-base catalysis.
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catalytic stereoselective 1 4 addition reactions using csf on alumina as solid base a heterogeneous platform for continuous flow synthesis of Glutamic Acid Derivatives
Angewandte Chemie, 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shu KobayashiAbstract:A novel methodology using CsF·Al2O3 as a highly efficient, environmentally benign and reusable solid base catalyst was developed to synthesize Glutamic Acid Derivatives via stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF·Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing undesired formation of pyrrolidine derivations via [3+2] cycloaddition, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR, 19F NMR, FT-IR, CO2-TPD, and XPS, and highly basic F from the Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using the solid base-catalyzed methodology.
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Calcium-Catalyzed Diastereo- and Enantioselective 1,4-Addition of Glycine Derivatives to α,β-Unsaturated Esters
Organic letters, 2008Co-Authors: Shu Kobayashi, Tetsu Tsubogo, Susumu Saito, Yasuhiro YamashitaAbstract:The first highly diastereo- and enantioselective catalytic asymmetric 1,4-addition reactions of a glycine Schiff base to β-substituted α,β-unsaturated esters have been developed. The reaction pathway was successfully controlled, and the desired 1,4-addition products were exclusively obtained with high enantioselectivities. The product obtained was converted to a 3-substituted Glutamic Acid Derivative by Acid hydrolysis.
Shū Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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catalytic stereoselective 1 4 addition reactions using csf on alumina as a solid base continuous flow synthesis of Glutamic Acid Derivatives
Angewandte Chemie, 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shū KobayashiAbstract:A novel methodology using CsF⋅Al2O3 as a highly efficient, environmentally benign, and reusable solid-base catalyst was developed to synthesize Glutamic Acid Derivatives by stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF⋅Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing the undesired formation of pyrrolidine derivations by [3+2] cycloadditions, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR and 19F NMR spectroscopy, FT-IR, CO2-TPD, and XPS. And highly basic F from Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using this solid-base catalysis.
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Catalytic Stereoselective 1,4‐Addition Reactions Using CsF on Alumina as a Solid Base: Continuous‐Flow Synthesis of Glutamic Acid Derivatives
Angewandte Chemie (International ed. in English), 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shū KobayashiAbstract:A novel methodology using CsF⋅Al2O3 as a highly efficient, environmentally benign, and reusable solid-base catalyst was developed to synthesize Glutamic Acid Derivatives by stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF⋅Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing the undesired formation of pyrrolidine derivations by [3+2] cycloadditions, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR and 19F NMR spectroscopy, FT-IR, CO2-TPD, and XPS. And highly basic F from Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using this solid-base catalysis.
Parijat Borah - One of the best experts on this subject based on the ideXlab platform.
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catalytic stereoselective 1 4 addition reactions using csf on alumina as a solid base continuous flow synthesis of Glutamic Acid Derivatives
Angewandte Chemie, 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shū KobayashiAbstract:A novel methodology using CsF⋅Al2O3 as a highly efficient, environmentally benign, and reusable solid-base catalyst was developed to synthesize Glutamic Acid Derivatives by stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF⋅Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing the undesired formation of pyrrolidine derivations by [3+2] cycloadditions, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR and 19F NMR spectroscopy, FT-IR, CO2-TPD, and XPS. And highly basic F from Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using this solid-base catalysis.
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Catalytic Stereoselective 1,4‐Addition Reactions Using CsF on Alumina as a Solid Base: Continuous‐Flow Synthesis of Glutamic Acid Derivatives
Angewandte Chemie (International ed. in English), 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shū KobayashiAbstract:A novel methodology using CsF⋅Al2O3 as a highly efficient, environmentally benign, and reusable solid-base catalyst was developed to synthesize Glutamic Acid Derivatives by stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF⋅Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing the undesired formation of pyrrolidine derivations by [3+2] cycloadditions, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR and 19F NMR spectroscopy, FT-IR, CO2-TPD, and XPS. And highly basic F from Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using this solid-base catalysis.
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catalytic stereoselective 1 4 addition reactions using csf on alumina as solid base a heterogeneous platform for continuous flow synthesis of Glutamic Acid Derivatives
Angewandte Chemie, 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shu KobayashiAbstract:A novel methodology using CsF·Al2O3 as a highly efficient, environmentally benign and reusable solid base catalyst was developed to synthesize Glutamic Acid Derivatives via stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF·Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing undesired formation of pyrrolidine derivations via [3+2] cycloaddition, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR, 19F NMR, FT-IR, CO2-TPD, and XPS, and highly basic F from the Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using the solid base-catalyzed methodology.
Shu Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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catalytic stereoselective 1 4 addition reactions using csf on alumina as solid base a heterogeneous platform for continuous flow synthesis of Glutamic Acid Derivatives
Angewandte Chemie, 2017Co-Authors: Parijat Borah, Yasuhiro Yamashita, Shu KobayashiAbstract:A novel methodology using CsF·Al2O3 as a highly efficient, environmentally benign and reusable solid base catalyst was developed to synthesize Glutamic Acid Derivatives via stereoselective 1,4-addition of glycine Derivatives to α,β-unsaturated esters. CsF·Al2O3 showed not only great selectivity toward 1,4-addtion reactions by suppressing undesired formation of pyrrolidine derivations via [3+2] cycloaddition, but also offered high yields for the 1,4-adduct with excellent anti diastereoselectivities. The catalyst was well characterized by using XRD, 19F MAS-NMR, 19F NMR, FT-IR, CO2-TPD, and XPS, and highly basic F from the Cs3AlF6 was identified as the most probable active basic site for the 1,4-addition reactions. Continuous-flow synthesis of 3-methyl Glutamic Acid Derivative was successfully demonstrated by using the solid base-catalyzed methodology.
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Calcium-Catalyzed Diastereo- and Enantioselective 1,4-Addition of Glycine Derivatives to α,β-Unsaturated Esters
Organic letters, 2008Co-Authors: Shu Kobayashi, Tetsu Tsubogo, Susumu Saito, Yasuhiro YamashitaAbstract:The first highly diastereo- and enantioselective catalytic asymmetric 1,4-addition reactions of a glycine Schiff base to β-substituted α,β-unsaturated esters have been developed. The reaction pathway was successfully controlled, and the desired 1,4-addition products were exclusively obtained with high enantioselectivities. The product obtained was converted to a 3-substituted Glutamic Acid Derivative by Acid hydrolysis.
I N Tyurenkov - One of the best experts on this subject based on the ideXlab platform.
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Correction of Alcohol-Induced Damage to Mitochondria in Cardiac and Cerebral Cells by Derivatives of Neuroactive Amino Acids
Bulletin of Experimental Biology and Medicine, 2020Co-Authors: T. A. Popova, V N Perfilova, I N Tyurenkov, I. I. Prokofiev, G. Kh. Khusainova, V. V. Bagmetova, I. V. Malyuzhenko, N. S. Ganzikova, G. P. Dudchenko, O. V. OstrovskiiAbstract:We studied LPO intensity and respiration of mitochondria in brain and heart cells of rats receiving 5% ethanol for 20 weeks and treated with Derivatives of neuroactive amino Acids. Chronic semicompulsory alcohol intoxication increased the concentration of LPO products in cardiac and cerebral mitochondria by 46 and 45% (diene conjugates), by 97 and 8% (diketones), and by 28 and 81% (malondialdehyde), respectively, reduced activity of antioxidant enzymes in cardiac and cerebral mitochondria by 24 and 45% (glutathione peroxidase) and by 22 and 26% (superoxide dismutase), respectively, and uncoupled the process of respiration and ATP synthesis, which manifested in a decrease in respiratory control (V_3/V_4 ratio according to Chance ). Glutamic Acid Derivative Neuroglutam (26 mg/kg) and GABA Derivative succicard (44 mg/kg) administered intraperitoneally daily for 28 days after termination of alcoholization decreased the levels of primary and secondary LPO products, up-regulated activity of antioxidant enzymes in mitochondria of the heart and brain, and moderated the mitochondrial dysfunction.
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Effect of Phenibut and Glufimet, a Novel Glutamic Acid Derivative, on Respiration of Heart and Brain Mitochondria from Animals Exposed to Stress against the Background of Inducible NO-Synthase Blockade
Bulletin of Experimental Biology and Medicine, 2017Co-Authors: V N Perfilova, T. A. Popova, I. I. Prokofiev, O. V. Ostrovskii, I. S. Mokrousov, I N TyurenkovAbstract:Increased oxygen consumption by heart and brain mitochondria in the absence of ADP and reduced mitochondrial respiration in the presence of ADP were observed in rats exposed to stress simulated by suspension by the dorsal neck skin fold for 24 h, which attests to uncoupling of substrate oxidation and ATP synthesis and can cause electron drain from the respiratory chain, formation of ROS, and oxidative damage to cell structures. Blockade of inducible NO synthase with aminoguanidine (single intraperitoneal dose of 50 mg/kg before stress exposure) increased coupling of respiration and oxidative phosphorylation in heart and brain mitochondria of rats exposed to immobilization-painful stress, which was especially pronounced in cardiomyocytes. The test compounds glufimet (single intraperitoneal dose of 29 mg/kg before stress exposure) and phenibut (single intraperitoneal dose of 50 mg/kg before stress exposure) limited stress-induced mitochondrial damage against the background of inducible NO synthase blockade and without it, which was seen from increased respiratory control ratio in comparison with that in untreated rats exposed to stress (control).
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Cardioprotective effect of a new Glutamic Acid Derivative, glufimet, under conditions of acute immobilization and painful stress in animals of different ages
Advances in Gerontology, 2016Co-Authors: V N Perfilova, N V Sadikova, I. I. Prokofiev, O. V. Inozemtsev, I N TyurenkovAbstract:The effect of 24-hour immobilization and painful stress on myocardial contractility was studied in young (6-month), middle-aged (12-month) and old (24-month) female rats. A reduction of the functional heart reserves was revealed. This manifested itself in a lower growth of the myocardial contraction and relaxation rates (+ dP/dt max and– dP/dt max), the left ventricular pressure (LVP), the maximum intensity of the functioning of the structures (MIFS) under conditions of increased pre- and afterload, and stimulation of the cardiac adrenergic receptors, which was especially pronounced in the group of 24-month-old rats. During the load tests, higher growth indicators of + dP/dt max,– dP/dt max, LVP, and MIFS were observed in animals of all age groups treated with glufimet at a dose of 29 mg/kg before and after stress; these indicators were most significant in older rats compared to young and middle-aged animals. A reference drug, Phenibut, improves the studied parameters equally in 6-, 12-, and 24-month-old females subjected to stress.
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effects of a new Glutamic Acid Derivative on myocardial contractility of stressed animals under conditions of nitric oxide synthesis blockade
Bulletin of Experimental Biology and Medicine, 2015Co-Authors: I N Tyurenkov, V N Perfilova, N V Sadikova, V M Berestovitskaya, O S VasilevaAbstract:Glufimet (Glutamic Acid Derivative) in a dose of 28.7 mg/kg limited the reduction of the cardiac functional reserve in animals subjected to 24-h stress under conditions of nonselective NO synthase blockade with L-NAME (10 mg/kg). Adrenoreactivity and increased afterload tests showed that the increment of myocardial contraction/relaxation rates, left-ventricular pressure, and HR were significantly higher in glufimet-treated stressed animals with NO synthesis blockade than in animals which received no glufimet. The efficiency of glufimet was higher than that of phenibut (the reference drug).
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Pharmacokinetic Properties of a New Glutamic Acid Derivative Glutaron
Bulletin of Experimental Biology and Medicine, 2015Co-Authors: L. A. Smirnova, V N Perfilova, A. F. Ryabukha, K. A. Kuznetsov, E. A. Suchkov, I N TyurenkovAbstract:Inhomogenous distribution of glutaron in organs and tissues was found after intravenous and peroral administration: the agent demonstrated high affi nity to organs with high degree of vascularization (lungs and heart) and elimination (kidney). Glutaron easily penetrates through the blood-brain barrier, which is consistent with its concentration in the adipose tissue.